WAFER INSPECTING METHOD

摘要

A method for inspecting a wafer is provided to discriminate defect from noise and to detect the defect by using a gray level signal value of a determination difference image. A normal pattern image of a unit inspection region and a pattern image to be inspected are multi-scanned with different inspection conditions(S210). The normal pattern image and the pattern image to be inspected are compared with each other by using same inspection conditions to store differences as difference images(S230). Gray level signal values of the stored difference images are calculated to generate a determination difference image(S240,S250). Defect and noise are determined by calculating a gray level signal value of the determination difference image(S270).